Hyunsik Jeong
I started my information security study from the university club called PLUS. I mainly focused on reverse engineering and cryptography while playing CTFs with PLUS, and achieved a lot of results including being the finalist of DEF CON CTF 4 years in a row. After graduation, I joined the graduate school of information security in KAIST, and wrote the master thesis about Qualcomm Hexagon emulators/decompilers analysis. Now, I work in S2W as a researcher, and play CTFs with perfect blue.
Work Experience
Researcher
- Ransomware research
- Cryptographic primitives analysis
- Offensive research
Software Engineer
- Mainly developed the blockchain called CodeChain (Link) in Rust
- Developed blockchain node APIs in TypeScript
- Studied various cryptographic methods used in blockchain technologies
Research Intern
- Interned at Netmarble AI Revolution Center (NARC)
- Studied reinforcement learning algorithms, including TRPO & PPO
Projects
Analysis of the Correctness of Qualcomm Hexagon Emulators and Decompilers via Differential Testing
For the master thesis. Analyzed Hexagon emulators (hexagon-sim from the Hexagon SDK, QEMU) and a decompiler (binja-hexagon) with the differential testing tool.
Verifiable Gacha System
A class project. Built a gacha platform with a VRF (verifiable random function). Users can fully access the gacha log, including verifiable random values. Still, only the server can generate random values.
Awards
1st place
1st place
1st place
Finalist
1st place
1st place
1st place
1st place
1st place
1st place
Finalist
Finalist
Finalist
1st place
Finalist
Finalist
Finalist
Finalist
Finalist
26th place
10th place
Gold prize
Written Challenges
pbctf
Yet Another PRNG, Yet Another RSA, Binary Tree (Link)